1. Field of the Invention
The invention relates to an alignment jig for an optical lens array, and more particularly to the alignment jig that can push to tightly engage a fiber plug and a corresponding lens socket so as to conveniently perform active optical alignment operations on the alignment jig.
2. Description of the Prior Art
As the development of the chip-on-board (COB) manufacturing technology, constructions of the optical transceiver have been greatly affected. In the art, the conventional manufacturing process of the optical transceiver is firstly to prepare the laser sensor chip into a transistor-outline-CAN (TO-CAN) package, the TO-CAN package is then aligned optically with a lens member so as to form an optical sub-assembly (OSA), and finally a complete optical transceiver set is formed by mounting an emitting OSA and a receiving OSA to the respective optical transceivers on the circuit board. Recently, as the progress of the art in COB, the related manufacturing process and the structuring of the related product have been greatly simplified. Practically, a modem laser transceiver can be obtained by simply mounting the sensor chip onto the optical transceiver of the circuit board, processing necessary wire bonding, and finally performing optical alignment upon the related lens members.
The alignment jig in the art is applied only to the OSA product having a sensor chip and a corresponding lens member, and can perform either an emitting alignment or a receiving alignment. On the other hand, for the direction of the optical fiber positioning is perpendicular to the optical alignment plane, the attachment between the optical fiber and the lens member is mainly contributed by the internal elasticity of the optical fiber. Nevertheless, recently, a sensor chip having simply an emitting end and a receiving end and an array chip having 12 emitting terminals and 12 receiving terminals to pair an array lens are found in the marketplace, of which the direction of the optical fiber positioning is parallel to the optical alignment plane. However, in these products, for the lens member and the fiber plug (MT fiber) are both small and thin (about 3˜4 mm), the holding in between is usually questionable. Because no relevant jig is available for ensuring firmly the attachment between the fiber plug and lens member during the optical alignment and further by considering the alignment rate for the optical paths, an improvement upon the alignment jig is inevitable.
Referring to FIG. 1A and FIG. 1B, an automatic passive array lens alignment machine is schematically shown. In this machine, a CCD 11 and a respective prism 12 are introduced to perform the optical alignment operation between the lens member 13 and an optical window of a sensor chip 14 on the circuit board 15. As shown in FIG. 1A, while the lens member 13 is optically aligned, the prism 12 is down shifted to allow the CCD 11 to use the upper reflective surface of the prism 12 to capture the image of the lens member 13 in order to perform the alignment. On the other hand, as shown in FIG. 1B, while the optical window of the sensor chip 14 is under the alignment operation, the prism 12 shifted upward so as to allow the CCD 11 to utilize the lower reflective surface to capture the image of the optical window of the sensor chip 14 in order to perform image comparing with the image of the lens member 13. However, the array lens alignment machine as shown in FIG. 1A and FIG. 1B can only perform a normal but not precision alignment due to mechanical displacement tolerance, CCD imaging bias, material difference between the lens member and the sensor chip, and so on. Actually, though the modem automatic passive array lens alignment technology may contribute a satisfied yield of alignment, yet a-μm scale of bias between the lens member and the optical window of the sensor chip is anyway inevitable. In addition, the aforesaid machine is expensive and not a popular technique that can be arbitrarily provided.